思路

立方体有6个面，由于OpenGL es的特性，每个面只能有两个三角形组成，一个三角形有三个顶点，在不考虑使用顶点索引的情况下，一共需要36个顶点立方体，需要开启深度测试和光源着色器旋转立方体，需要做矩阵变换，使用固定着色器的

baseEffect.transform.modelviewMatrix可以旋转矩阵 数据

typedef struct {GLKVector3 positionCoord; //顶点坐标GLKVector2 textureCoord; //纹理坐标GLKVector3 normal ; //法线，与光源相关，法线是垂直于两个向量的向量，} LLVertex;

需要的属性

@property(nonatomic,strong) GLKView *glkView;//渲染OpenGL的View@property(nonatomic,strong) GLKBaseEffect *baseEffect;// 固定着色器@property(nonatomic,assign) LLVertex *vertices; //顶点指针@property(nonatomic,strong) CADisplayLink *displayLink;@property(nonatomic,assign) NSInteger angle; // 旋转角度@property (nonatomic, assign) GLuint vertexBuffer; //顶点缓冲区id

步骤

1.初始化context、顶点、glkView、官员等

2.添加定时器、更新角度，并进行矩阵变换

#import "ViewController.h"#import <GLKit/GLKit.h>typedef struct {GLKVector3 positionCoord; //顶点坐标GLKVector2 textureCoord; //纹理坐标GLKVector3 normal ; //法线，光照} LLVertex;static NSInteger const kCoordCount = 36;@interface ViewController ()<GLKViewDelegate>@property(nonatomic,strong) GLKView *glkView;@property(nonatomic,strong) GLKBaseEffect *baseEffect;// 固定着色器@property(nonatomic,assign) LLVertex *vertices;@property(nonatomic,strong) CADisplayLink *displayLink;@property(nonatomic,assign) NSInteger angle;@property (nonatomic, assign) GLuint vertexBuffer;@end@implementation ViewController- (void)viewDidLoad {[super viewDidLoad];[self commonInit];[self addCADisplayLink];}-(void)commonInit{//设置上下文EAGLContext *context = [[EAGLContext alloc] initWithAPI:kEAGLRenderingAPIOpenGLES2];[EAGLContext setCurrentContext:context];//创建GLKView并设置代理CGRect frame = CGRectMake(0, 100, self.view.frame.size.width, self.view.frame.size.width);self.glkView = [[GLKView alloc] initWithFrame:frame context:context];self.glkView.backgroundColor = [UIColor clearColor];self.glkView.delegate = self;self.glkView.drawableDepthFormat = GLKViewDrawableDepthFormat24;glDepthRangef(1, 0);[self.view addSubview:self.glkView];NSString *imagePath = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:@"lufei.jpg"];UIImage *image = [UIImage imageWithContentsOfFile:imagePath];//设置纹理参数NSDictionary *options = @{GLKTextureLoaderOriginBottomLeft : @(YES)};//倒转图片GLKTextureInfo *textureInfo = [GLKTextureLoader textureWithCGImage:[image CGImage]options:optionserror:NULL];//初始化固定着色器self.baseEffect = [[GLKBaseEffect alloc] init];//传入纹理到固定着色器self.baseEffect.texture2d0.name = textureInfo.name;self.baseEffect.texture2d0.target = textureInfo.target;//开启光源self.baseEffect.light0.enabled = YES;self.baseEffect.light0.diffuseColor = GLKVector4Make(1, 1, 1, 1);//漫反射self.baseEffect.light0.position = GLKVector4Make(-0.5, -0.5, 5, 1);//光源位置//开辟顶点空间self.vertices = malloc(sizeof(LLVertex)* kCoordCount);// 前面self.vertices[0] = (LLVertex){{-0.5, 0.5, 0.5}, {0, 1}, {0, 0, 1}};self.vertices[1] = (LLVertex){{-0.5, -0.5, 0.5}, {0, 0}, {0, 0, 1}};self.vertices[2] = (LLVertex){{0.5, 0.5, 0.5}, {1, 1}, {0, 0, 1}};self.vertices[3] = (LLVertex){{-0.5, -0.5, 0.5}, {0, 0}, {0, 0, 1}};self.vertices[4] = (LLVertex){{0.5, 0.5, 0.5}, {1, 1}, {0, 0, 1}};self.vertices[5] = (LLVertex){{0.5, -0.5, 0.5}, {1, 0}, {0, 0, 1}};// 上面self.vertices[6] = (LLVertex){{0.5, 0.5, 0.5}, {1, 1}, {0, 1, 0}};self.vertices[7] = (LLVertex){{-0.5, 0.5, 0.5}, {0, 1}, {0, 1, 0}};self.vertices[8] = (LLVertex){{0.5, 0.5, -0.5}, {1, 0}, {0, 1, 0}};self.vertices[9] = (LLVertex){{-0.5, 0.5, 0.5}, {0, 1}, {0, 1, 0}};self.vertices[10] = (LLVertex){{0.5, 0.5, -0.5}, {1, 0}, {0, 1, 0}};self.vertices[11] = (LLVertex){{-0.5, 0.5, -0.5}, {0, 0}, {0, 1, 0}};// 下面self.vertices[12] = (LLVertex){{0.5, -0.5, 0.5}, {1, 1}, {0, -1, 0}};self.vertices[13] = (LLVertex){{-0.5, -0.5, 0.5}, {0, 1}, {0, -1, 0}};self.vertices[14] = (LLVertex){{0.5, -0.5, -0.5}, {1, 0}, {0, -1, 0}};self.vertices[15] = (LLVertex){{-0.5, -0.5, 0.5}, {0, 1}, {0, -1, 0}};self.vertices[16] = (LLVertex){{0.5, -0.5, -0.5}, {1, 0}, {0, -1, 0}};self.vertices[17] = (LLVertex){{-0.5, -0.5, -0.5}, {0, 0}, {0, -1, 0}};// 左面self.vertices[18] = (LLVertex){{-0.5, 0.5, 0.5}, {1, 1}, {-1, 0, 0}};self.vertices[19] = (LLVertex){{-0.5, -0.5, 0.5}, {0, 1}, {-1, 0, 0}};self.vertices[20] = (LLVertex){{-0.5, 0.5, -0.5}, {1, 0}, {-1, 0, 0}};self.vertices[21] = (LLVertex){{-0.5, -0.5, 0.5}, {0, 1}, {-1, 0, 0}};self.vertices[22] = (LLVertex){{-0.5, 0.5, -0.5}, {1, 0}, {-1, 0, 0}};self.vertices[23] = (LLVertex){{-0.5, -0.5, -0.5}, {0, 0}, {-1, 0, 0}};// 右面self.vertices[24] = (LLVertex){{0.5, 0.5, 0.5}, {1, 1}, {1, 0, 0}};self.vertices[25] = (LLVertex){{0.5, -0.5, 0.5}, {0, 1}, {1, 0, 0}};self.vertices[26] = (LLVertex){{0.5, 0.5, -0.5}, {1, 0}, {1, 0, 0}};self.vertices[27] = (LLVertex){{0.5, -0.5, 0.5}, {0, 1}, {1, 0, 0}};self.vertices[28] = (LLVertex){{0.5, 0.5, -0.5}, {1, 0}, {1, 0, 0}};self.vertices[29] = (LLVertex){{0.5, -0.5, -0.5}, {0, 0}, {1, 0, 0}};// 后面self.vertices[30] = (LLVertex){{-0.5, 0.5, -0.5}, {0, 1}, {0, 0, -1}};self.vertices[31] = (LLVertex){{-0.5, -0.5, -0.5}, {0, 0}, {0, 0, -1}};self.vertices[32] = (LLVertex){{0.5, 0.5, -0.5}, {1, 1}, {0, 0, -1}};self.vertices[33] = (LLVertex){{-0.5, -0.5, -0.5}, {0, 0}, {0, 0, -1}};self.vertices[34] = (LLVertex){{0.5, 0.5, -0.5}, {1, 1}, {0, 0, -1}};self.vertices[35] = (LLVertex){{0.5, -0.5, -0.5}, {1, 0}, {0, 0, -1}};//顶点数据传入GPUglGenBuffers(1, &_vertexBuffer);glBindBuffer(GL_ARRAY_BUFFER, _vertexBuffer);glBufferData(GL_ARRAY_BUFFER, sizeof(LLVertex) * kCoordCount, self.vertices, GL_STATIC_DRAW);//纹理坐标传入GPUglEnableVertexAttribArray(GLKVertexAttribPosition);glVertexAttribPointer(GLKVertexAttribPosition, 3, GL_FLOAT, GL_FALSE, sizeof(LLVertex), NULL + offsetof(LLVertex, positionCoord));//纹理传入GPUglEnableVertexAttribArray(GLKVertexAttribTexCoord0);glVertexAttribPointer(GLKVertexAttribTexCoord0, 2, GL_FLOAT, GL_FALSE, sizeof(LLVertex), NULL + offsetof(LLVertex, textureCoord));//法向量传入GPUglEnableVertexAttribArray(GLKVertexAttribNormal);glVertexAttribPointer(GLKVertexAttribNormal,3,GL_FLOAT,GL_FALSE,sizeof(LLVertex),NULL + offsetof(LLVertex, normal));}-(void) addCADisplayLink{self.angle = 0;self.displayLink = [CADisplayLink displayLinkWithTarget:self selector:@selector(update)];[self.displayLink addToRunLoop:[NSRunLoop mainRunLoop] forMode:NSRunLoopCommonModes];}-(void)update{self.angle = ( self.angle + 1) % 360;self.baseEffect.transform.modelviewMatrix = GLKMatrix4MakeRotation(GLKMathDegreesToRadians(self.angle), 0.3, 1, 0.7);[self.glkView display];}- (void)glkView:(GLKView *)view drawInRect:(CGRect)rect{glEnable(GL_DEPTH_TEST);glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);[self.baseEffect prepareToDraw];glDrawArrays(GL_TRIANGLES, 0, kCoordCount);}- (void)dealloc {if ([EAGLContext currentContext] == self.glkView.context) {[EAGLContext setCurrentContext:nil];}if (_vertices) {free(_vertices);_vertices = nil;}if (_vertexBuffer) {glDeleteBuffers(1, &_vertexBuffer);_vertexBuffer = 0;}//displayLink 失效[self.displayLink invalidate];}@end

Demo地址